Disazo-dyestuffs



United States Patent 6 DISAZO-DYESTUFFS Hans Liechti, Riehen, Switzerland, assignor to Ciba Limited, Basel, Switzerland, a Swiss firm No Drawing. Application May 15, 1952, Serial No. 288,051

Claims priority, application Switzerland June 11, 1951 13 Claims. (Cl. 260-453) This invention provides new disazo-dyestuifs, for example, the dyestufi of the formula which contain at least two and at most three sulfonic acid groups and in the form of the free acids correspond to the general formula H o- N= NH-o 0Q HO O G ('11 in which Y represents a halogen atom, a hydroxyl group or an amino group, which latter group may contain substituents.

The disazo-dyestuffs of the Formula 2 are made by condensing together by means of phosgene or a cyanuric halide two monoazo-dyestufis of the formulae NH HO 0 d in which R1 and R2 have the meanings given above, and, if desired, converting the third remaining halogen atom bound to the cyanuric ring into a hydroxyl group or an amino group which may contain substituents.

The monoazo-dyestufis of the Formula 3 can be made by'coupling a diazotized l-amino-2-chloro-4-nitrobenzene with 1-hydroxybenzene-2-carboxylic acid, sulphonating the resulting 2'-chloro-4-nitro-4hydroxy-l:l'-azo-benzene-3-carboxylic acid and then reducing the nitro group to an amino group, then acylating the resulting amino group with metaor advantageously para-nitrobenzoyl chloride, and finally reducing the nitro group to an amino group.

As monoazo-dyestuifs of the Formula 4 there are used, for example, those of the formula OOH in which R1 represents a benzene radical free from sul- OaH Cl COOH tonic acid groups and bound in para-position to the HzN- and N=N- groups, for example, a benzene radical of the formula in which Z1 represents a hydrogen atom or a methyl or methoxy group, and Z2 represents a hydrogen atom or a methyl or methoxy group or a chlorine atom. Such mono-azo-dyestuifs can be made, for example, by coupling diazotized 4-amino-l-hydroxybenzene-Z-carboxylic acid-6-sulfonic acid with an amine of the benzene series capable of coupling in para-position relatively to the amino group, such as aminobenzene, l-amino-Z- or -3- methylbenzene, l-amino-Z:S-dimethylbenzene, l-amino 2- or -3-methoxy-benzene, 1-amino-2:5-dimethoxy-benzene or l-amino-2-methoxy-S-methylbenzene.

The latter coupling is carried out in known manner advantageously in a weakly acid medium, for example,

a medium rendered acid with acetic acid. Amines which are difficult to'couple such, for example, as aminobenzene, are advantageously coupled in the form of their so-called w-methane-sulfonic acids, and the w-methane-sulfonic acid group is subsequently split off.

It is also of advantage to use as the starting material of the Formula 4 2-chloro-4-amin0-4-hydroxy-l:l-azo benzene-3-carboxylic acid-S-sulfonic acid, for which a method of preparation is described above.

There also come into consideration monoazo-dyestutis of the Formula 4 in which, in contradistinction to those mentioned above, the sulfonic acid group is bound to the radical R1, Compounds of this type can be made by coupling a diazotized para-nitro-amino-benzene sulfonic acid in alkaline solution with a 1-hydroxybenzene-Z-carboxylie acid, and then reducing the nitro group to an amino group.

The condensation of the amino-monoazo-dyestufis of the Formulae 3 and 4 to form asymmetrical urea derivatives by means of pho sgene is advantageously conducted in an aqueous medium, preferably with the dyestutf in the form of its alkali salt and with the addition to the phosgenizing mixture of an acid-binding agent, for example, an alkali carbonate, alkali acetate or an alkali orthophosphate or pyrophosphate, in order by the buffering action of these additions to maintain the pH value ranging from about 9.5 to 5.5 which is especially favorable for the reaction with phosgene.

The condensation of the two dyestuffs of the Formulae 3 and 4 with a cyanuric halide, for example, cyanuric bromide, or advantageously cyanuric chloride, and also the condensation of the third halogen atom remaining in the cyanuric radical, may with advantage be conducted in an aqueous medium. The two amino-azo-dyestuffs are advantageously reacted in succession with the cyanuric halide, for example, the dyestuff of the Formula 3 may be reacted first and then the dyestuli of the Formula 4. In the so-obtained binary condensation product the remaining halogen atom bound to the triazine nucleus may be transformed into a hydroxy group or an NHz-group. When the resulting binary condensation product is to be condensed at the third halogen atom of the cyanuric radical with an amine, it is of advantage to use for this purpose a simple amine of the benzene series, for example, aminobenzene or an aminobenzene sulfonic acid. As already stated in connection with the condensations with the cyanuric halide, the pH value and/or the reaction temperature is advantageously progressively increased at each stage of condensation.

The new dyestuffs of the invention, which correspond to the Formula 2 above, are suitable above all for dyeing or printing cellulose materials, such as cotton, linen and artificial silk or staple fibers of regenerated cellulose. Especially valuable dyeings, which are distinguished by their very good fastncss to washing and light, are produced by treating the dyestuffs on the fiber or partly on the fiber and partly in the dye-bath with an agent yielding metal. It is of advantage to use, for example, the process of U. S. Patent No. 2,148,659, in which there is, carried out in the same bath first the dyeing and then the treatment with an agent yielding metal. As agents yielding metal there come into consideration preferably agents yielding copper, and especially those which are stable to alkaline solutions, such as complex copper tartrates.

Very valuable dyeings are produced by working according to the processes in which a dyeing or print produced with the metal-free dyestuff is after-treated with an aqueous solution which contains a basic condensation product of formaldehyde with a compound containing at least once the atomic grouping Example 1 17.25 parts of l-amino-2-chloro4-nitrobenzene are diazotized in known manner and coupled with 13.8 parts of vl-l:lydroxybenzene-Z-carboxylic acid in a weakly acid to alkaline solution.

32.15 parts of the separated and dried dyestuff are introduced into 120 parts of fuming sulfuric acid having a content of free anhydride of 20 per cent, and the whole is heated while stirring well for hours at 95-l00 C. After cooling, the reaction mass is poured on to ice, stirred for a few .hours and filtered. The dyestuff paste is dissolved in 350 parts of hot water, and filtered, a small portion of the unsulfonated dyestult remaining on the filter. The filtrate is mixed with sodium hydroxide solution of 30 per cent. strength until the reaction becomes alkaline to Brilliant Yellow paper and the sodium salt of the dystufi is precipitated with sodium chloride.

The dyestuff paste is dissolved in 500 parts of Water and the nitro group is converted into an amino group by means of 9.2 parts of sodium hydrosulfidc at 60-70 C., and the aminoazo-dyestutf is precipitated with sodium chloride and separated by filtration.

The dyestuff paste is dissolved in 800 parts of water, and 16 parts of anhydrous sodium carbonate are added to the solution, and then 26 parts of para-nitrobenzoyl chloride dissolved in 50 parts of acetone are run in at 4040" C. When the condensation has finished, the precipitated dyestuff is filtered off, and the nitro group is converted into an amino group in the usual manner by means of sodium sulfide at about 6065 C.

49 parts of the separated and dried dyestufl, or a corresponding amount of the dyestufl? paste, and 37.1 parts of 4' amino 2 chloro 4 hydroxy lzl azobenzene-3-carboxylic acid-5-sulfonic acid are treated with phosgene in known manner in the presence of sodium carbonate as an acid-binding agent and sodium acetate as a butter substance until amino groups can no longer be detected. The completely precipitated dyestuff is filtered off and dried. The new dyestutf is a yellow-brown powder which dissolves in water with a yellow coloration and dyes cotton and regenerated cellulose pure greenish yellow tints, having good properties of wet fastness and fastness to light. By the single bath or Z-bath aftercoppering process there are obtained greenish yellow tints of high purity and having very good properties of wet fastness and fastness to light.

Instead of 4 (4" amino) benzoylamino 2'-chloro- 4 hydroxy 1:1 azobenzene 3 carboxylic acid 5- sulfonic acid there may be used 4-(3"-amino)-benzoylamino 2 chloro 4 hydroxy 1:1 azobenzene- 3-carboxylic acid-S-sulfonic acid, a dyestuff being obtained which possess valuable properties similar to those of the disazo-dyestuif first described in this example.

Example 2 A solution of 49 parts of 4-(4"-amino)-benzoylamino- 2-chloro-4-hydroxy-1 l-azobenzene-3-carboxylic acid-5 sulfonic acid and 10.6 parts of sodium carbonate in 2000 parts of water is poured at 5 C. in the course of 10 minutes into a suspension of 18.4 parts of cyanuric chlo ride in a small amount of ice water, and the hydrochloric acid formed is neutralized with a solution of 8.4 parts of sodium bicarbonate in 30 parts of water. After 1 hour the condensation is finished. A solution, having a temperature of 40 C. of 37.1 parts of 4-amino-2-chloro- 4 hydroxy 1:1 azobenzene 3 carboxylic acid 5- sulfonic acid in 1000 parts of water is then poured in, and the temperature is maintained at 3035 C. for 12 hours while stirring well. During this period, a solution of 10 parts of sodium bicarbonate in 35 parts of water is introduced dropwise. 20 parts of aniline are then poured in, the whole is heated for 2 hours at -90 C., 10.6 grams of sodium carbonate are strewn in, and the condensation product is salted out with sodium chloride.

The new dyestufi is a yellow powder which dissolves in water with a yellow coloration, and dyes cotton and regenerated cellulose very 'pure yellow tints. By the single bath or ,2-bath after-coppering process there are obtained yellow tints of very good ,fastness to washing and light.

By using, instead of aniline, aminobenzene-3- or -4- sulfonic acid there are obtained dyestuffs having three sulfonic acid groups in the molecule. These dyestuffs possess the same good properties as that produced with aniline.

The dyestufis produced either by leaving the third re-v ess there are obtained yellow tints of very good fastnes's active chlorine atom in the cyanuric radical unreacted to washing and light. v or by replacing the chlorine atom by a hydroxyl group The 4' amino 2':5' dimethyl 4 hydroxy 1:1- by hydrolysis with an alkaline agent, possess the same azobenzene 3 carboxylic acid 5 sulfonic acid used good dyeing properties as the dyestuffs previously de- 5 for producingthe above dyestufr is advantageously prescribed. pared by coupling diazotized 4-amino-1-hydroxybenzene- Example 3 Z-carboxylic acid-6sulfonic acid with 1-amino-2:5-dimethylbenzene in an acetic acid solution.

49 Parts of the Y Further valuable disazo-dyestutfs are made, by using, 4 Y Y aZObeIlZene 3 carboxylic acid 10 instead of the amino-monoazo-dyestuff from 1-amino-2:5- Sulfonic acid Produced as described in a p 1 n dimethylbenzene, for producing the urea compound the Parts of y ycorresponding monoazo-dyestufi from the above menboxylic acid-2'-sulfonic acid are linked together in the i d di compound d one f h f ll i azo usual manner y means of phosgene form all y components: Aminobenzene, l-amino-2- or 3-methylmetrical urea. benzene, 1-amino-2:S-dimethoxybenzene, l-arnino-Z- or The completely precipitated dyestulf is separated by -3 fh b d 1 i -g h .5- l filtration and dried. It is a brown powder which disb solves in water with an orange coloration, and dyes cot- Instead of 4' 4" i -b i 1 .2'- 1 .4. ton and regenerated cellulose y P Yellow Y hydroxy-l:1' azobenzene-3ceirbbXylic acid 5 sulfonic the single bath or 2-bath after-coppering process there id, 4 (3" amino) benzoylamino-Z'-chloro-4-h are obtained yellow tints of very good fastness'to washd 1;1' azobenzene-3-carboxylic id-5- 1f i g and lightacid may be condensed with 4-amino-2:5-dimethyl-4- Instead Of amino 4 Y Y alobenhydroxy-l:1-azobenzene-3carboxylic acid-S-sulfonic acid zene 3 carboxylic acid 2' sulfonic acid, there may t f h asymmetrical urea" be used 4 amino 4 hydroxy 5 methyl 1:1 azobenzene 3 carboxylic acid 2' sulfonic acid. The two amino-monoazo dyestuifs mentioned above can be made by coupling diazotized 1-amino-4-nitrobenzenesulfonic acid with hydroxybenzene-Z-carboxylic acid or Example 5 100 parts of cotton are entered at 50 C. into a dyebath containing in 4000 parts of water 2 parts of anhydrous sodium carbonate and 0.7 part of the dyestufr' obl-hydroxy-G methylbenzene 2 carboxyllc acid in alkaline tainable as described in the first five paragraphs of E $5 and then redilcmg the mm, group to an ammo ample 1. The temperature is slowly raised to the boil, 30 parts of crystalline sodium sulfate are added, and dye- By using instead of 4-am1no-4-hydroxy-1:1azoben- 3 zene-3-carboxylic acid.-2'-sulfonic acid, 4'-amino-4-hyi i T g I 1 2 ggl g bath droXy 1:1 azobenzene 3 carboxylic acid 3 sulgg gz i fi g g g g d $5 2 fonic acid there is obtained a dyestufivhaving the same P 1 1 b n S dyeing properties. This amino-azocornpound may be i' g treated or /2 houltlat g 18 then Prepared by coupling 1amino-4diazobenzene-2-sulfonic 2 gg gsfg g sf gi g z sg g i dyeacrd with 1hydroxybenzene-Z-carboxylrc acid 1n al- 40 What is claimed is:

kahne Solutlon' I 1. A disazo-dyestuif which contains at least two and Instead of 4'-(4"-amino)benzoylarnino-Z'chloro-4- hydroxy azobenzene 3 carboxylic acid 5 sub at most three sulfomc acid groups and corresponds to the tonic acid, there may be used for the synthesis of the formula" 1 Hos? l v I NH-XEN-Ri- N =NR2 H000 o1 asymmetrical urea derivative 4-(3"-amino)=benzoylamii in which the carbon atoms of the benzene nucleus I bound no 2 chloro 4 hydroxy 1:1 azobenzene 3 carto the OC and NH-- groups are separated from boxylic acid 5 sulfonic acid. one another by at least one carbon atom, R1 represents a benzene radical bound in para-position to the groups HN- and N=N, and R2 represents the radical 49 parts of 4 (4 amino) benzoylamino 2- of a 1-hydroxybenzene-Z-carboxylic acid bound in 4- chloro 4- hydroxy 1:1 azob'enzene' 3' 'carboxylic a position to the azo linkage, one of the radicals R1 and R2 acid-S-sulfonic acid prepared as described in Example 1 containing a sulfonic acid group, and X represents a memand 36.5 parts of 4-amino-2:5'-dimethyl-4-hydroxy-1:l'- ber selected from the group consisting of a CO radiazobenzene-3-carboxylic acid-5 sulfonic acid are treated cal and atriazine radical. with phosgene in a weakly alkaline solution until primary G0 2. A disazo-dyestutf which contains at least two and amino groups can no longer be detected. at most three sulfonic acid groups and corresponds to the The urea derivative obtained from the above compoformula Example 4 i gno N=N- NH0C 1 Q N 5 NHC C-HNRi-N=NR2 H00 1 l l i HN-Y nents, after it has been completely precipitated, is sepiii'whi h the carbon atomsof the benzene nucleus I bound arated by filtration, and dried. It is a' brown powder to the"- OC- and groups are separated from which dissolves in water with an-orange coloration and one another by at least ,one carbon atom, R1 represents dyes cotton and regenerated cellulose very pure yellow a benzene radical bound in para-position to the groups tints. By the single bath and 2-bath after-coppering proc- NH and N=N, R2 represents the radical of a 8 l-hydroxybenzene-Z-carboxylic acid bound in 4-position in which the carbon atoms of the benzene nucleus I bound to the azo linkage, one of the radicals R1 and Rz containto the -OC and -NH-- groups are separated from ing a sulfonic acid group and Y represents a benzene radione another by at least one carbon atom, R1 represents cal. a benzene radical bound in para-position to the groups 3. A disazo-dyestuff which contains two sulfonic acid 5 .NH--- and -N=N-, and Y represents a benzene groups and corresponds to the formula radical.

H01? HO-N=N NH-OC I Z 1 NH-C OHN-Rr-N=N-Rz H00 01 in which the carbon atoms of the benzene nucleus I bound 5. A disazo-dyestutf which contains at most three sulto the OC- and -NH-- groups are separated from tonic acid groups and corresponds to the formula Hols HO- N=N NH-OC N 6 A} NHC C-HN N=n- OH H00 1 II N N (l;

1 OOH HlI-Y one another by at least one carbon atom, R1 represents a in which the carbon atoms of the benzene nucleus I bound benzene radical bound in para-position to the group to the and groups are separated f NH and N:N R2 .reprqsents the .radical 9? a one another by at least one carbon atom, and wherein Y l-hydroxy benzene-Z-carboxyhc and bound in 4-pos1t1on 30 represents a benzene radical.

to the azo-linkage, one of the radicals R1 and R2 containing a ulfoni a id group 6. The disazo-dyestutf of the formula HO: S 01 S 01H 1 l N l H O N=N- NH-C O Nil-CI ("L-EN N=N- O H I N N HO O O C l O O H 4. A disazo-dyestulf which contains at most three sulfonic acid groups and corresponds to the formula V (l: A NH-C OHN-Rr-N=N OH H o 0 1 l 1 i O OH H--N-Y 7. The disazo-dyestutf of the formula HO: S 01 5 0111 I N H 0- N=N- NH-O 0- N H-(|J ("J-HN N=N- -0 H N I& (E H O O C l 0 O H g OaH 8. A disazo-dyestuff corresponding to the formula COOH in which the carbon atoms of the benzene nucleus I bound to the OC and NH- groups are separated from one another by at least one carbon atom, R1 represents a benzene radical bound in para-position to the group NH- and N=N and free from sulfonic 5 acid groups.

9. A disazo-dyestutf corresponding to the formula HOlS in which the carbon atoms of the benzene nucleus I bound to the OC and NH groups are separated HOrS Hood

from one another by at least one carbon atom, Z1 repre- HOs? Cl sents a member selected from the group consisting of a from one another by at least one carbon atom.

10 hydrogen atom, a methyl and a methoxy group and Z2 represents a member selected from the group consisting of a hydrogen and a chlorine atom, a methyl and a methoxy group.

10. A disazo-dyestuff of the formula I S 03H I CI 00011 in which the carbon atoms of the benzene nucleus I bound to the OC and NH groups are separated SOgH 11. The disazo-dyestuif of the formula 12. The disazo-dyestufi of the formula O HO N=N ONH CO NHJLHNQMQOH HO O A) l O OH 13. The disazo-dyestuif of the formula CH: $00K References Cited in the file of this patent UNITED STATES PATENTS 2,283,261 Kaiser 2,341,791 Kaiser 2,375,561 Kaiser 2,667,477 Liechti May 19, 1942 Feb. 15, 1944 May 8, 1945 Jan. 26, 1954 

1. A DISAZO-DYESTUFF WHICH CONTAINS AT LEAST TWO AND AT MOST THREE SULFONIC ACID GROUPS AND CORRESPONDS TO THE FORMULA 